Fluid operated ptjmp



SHQ: Heard* 5 Sheets-Sheet l G. S. KNOX FLUID GPERATED Pour Filed Jan. 5. i933 Oct. 23, 1934.

Oct. 23, 1934. G. s. KNox 1,977,727

FLUID OPERATED Pmi? Filed Jan. 3, 1953 5 Sheets-Sheet 2 WHW Y L W W nun www 4 ,m f WMI rrd I /fu f Filed Jan. 3, 1933 5 Sheets-Sheet 3 Si! Zo: aulne 42 oct. 23, 1934. s KNOX 1,977,727

FLUID OPERATED PUMP Filed Jan. 3. 1933 5 Sheets-Sheet 4 zo 334%/ f/a" l AUX X Oct. 23, 1934. G, s, KNox FLUID OPERATED PUMP Filed Jan. 3. 19.33 5 Sheets-Sheet 5 L r A v f .Patented Oct. 23, 1934 umrao .srarss sa-TENT carica 1,977,727 FLUID orEaATsn PUMP Granville S. Knox, Los Angeles, Calif. applicati@ January 3,1933, sei-iai No. 649,885

\ 13 claims.. (or 10a- 46) i 'I'his invention relates to iiuid operated pumps and has particular reference to what are commonly termed rodless pumps for pumping deep wells, especially oil wells.

In my United States Patent No. 1,909,493, issued May 16, 1933, there is disclosed a fluid operated pump incorporating a basically new feature in pump design. Essentially, that pump -comprises a motor and pump piston assembly and a fluidpressure operated valve mechanism in which the movement of the piston assembly and the valve mechanism in proper, timed sequence,ris insured by so proportioning the faces of the valve and piston assemblies that the ratio of the opposite 15 areas of valve surface exposed to operating uid and exhaust iiuidrespectively, is always greater` than the ratio of the opposite areas of piston surface simultaneously exposed to operating filuid and exhaust fluid, respectively this insures com- 90 plete movement of the valve to a desired new position before the piston assembly begins its next stroke. y

'Ihe pump constituting the present invention is a variation of that disclosed in the aforemen.

tioned prior patent. It incorporates the same basic principles of operation with the addition of refinements that make it more practicable and more eilicient in operation.-

An object of the Apresent invention isto provide a fluid operated pump having the positive and. reliable valve action characterizing my rodless pump as disclosed in my Patent No. 1,909,493, that displaces equal volumes of exhaust fluid and pumped'nuid on both strokes. y e

Another object of theinvention is to provide a pump having the positive and reliable valve action of my original pump, in which the pump is positioned below the motortto permit using a conventional gas anchor on the pump.

o A feature of the invention is the novel means -and method of connecting the lower end of the high pressure tubing 'extending down through the weil to the pumpl whereby the high pressure tubing-may be readily released from the pump vand vented into the surrounding'exhaust tubing to permit drainage of the oil from the high pressure tubingor to blow out sand from the passages .immediately above the pump.

e Another feature lies in the particular construction ofthe pump, wherein a double seal against leakage from the high pressure passages of the pump is provided.

Other features of the invention will be appar- -e`nt from the following detailed description in which reference is made to the-accompanying drawings.

. Figure 11 and showing consecutively lower por- -65 tions of the pump.

Figure 9 is a sectional elevational view of portions of the pump, this section being taken in the plane IX-IX of Figure 12, and showing one set of passages within the pump.

Figure 10 is a sectional view of -the'pump taken in theplane X-X of Figure 14, and showing the course of another set of passages within the pump.

Figures l1, 12, 13, 14, 15, 16, 17 and 18 are 75- cross sectional views of the pump taken in the plane designated with corresponding reference numerals in Figures 3, 4, 5, and 6.

Figures 19 and 20 are simplified schematic diagrams for illustrating the operation of the pump.

Theory of operation A complete understanding of the construction and operation of my pump can best be obtained y first following through the general construotion and theory of operation with 'reference to the diagrammatic views constituting Figures 19 and 20, respectively. These views are identical, except that Fig. 19 shows the piston assembly and valve in their lowe'rmost positions (at the end of 90 their down strokes) and Figure'20 shows the pis' ton assembly and valve in their upper positions (which they assume at the end of their 'up' strokes).

Referring now to Fig. 19, I have shown a pump' 95 cylinder l and a motor cylinder 2 positioned coaxially therewith and immediately thereabove. A pumpl piston 3 is positioned in the -pump cylinder and a motor piston 4 in the motor cylinder, both rigidly mounted on a common piston rod 100 5 extending-not only between the motor and pump pistons 4 and 3 but upwardly beyond the motor cylinder 2 for a substantial distance through a4 valve chamber 6 and terminating in a passage 7 communicating with the exterior ofthe pump. The lower end of the pump cylinder 1 is provided with an inlet valve 8 and the pump piston 3 is provided with an upwardly opening valve 9. The upper end of the pump cylinder 1 communicates through a passage l0 with the space between an 110 2 1,977,727 inner tube 1l and outer tube 12 extending to the surface of the well. It will be apparent that as the pump piston 3 moves downwardly the oil-or fluid inthe cylinder therebelow' will beforced past the valve 9 in the piston into-the cylinder space above the piston and due to the displacement-of the piston rod 5 some of this fluid will be forced up through the passage into the exhaust pipe 12. Onthe subsequentupward stroke the pump piston 3 will force the fluid in the cylinder thereabove through the passage 10 into the exhaust pipe 12.

By making the area of the piston rod'5 equal to half the area of the pump piston 3, the pump will displace equal volumes of fluid through pas` sage 10 into the exhaust pipe 12 on each stroke.

To supply operating uid to and exhaust fluid from the motor cylinder 2, passages 18 and 14 are provided extending from respective opposite ends of the motor cylinder` 2 to the valve chamber 6. A pair of ports and 16 respectively conneet the valve chamber l6 with the exhaust passage 16 and an inlet passage 17 connects the 'sive chamber 6 with the pressure pipe 11 which supplies operating uid under pressure from the surface of the earth. The operating fluid may be forced down through the tube 11 by any suitable pump. l

' Positioned within the valve chamber 6v is a piston valve indicated generally at 18 which surrounds the extended upper portion of the piston 'rod 5. Valve 18 is provided with four outwardly extending shoulders 19, 20, 21 and 22, which seal with the walls of the chamber 6. The inner `wa1l of the valve 18 seals with the piston rod 5.

except at the point between the shoulders 20 and 21. Y. It will be observed that the four shoulders 19, 20, 21 and 22, on valve 18, define three concentric passages or pockets 23, 24 and 25,.which pockets serve when the valve is in various positions to interconnect in a desired manner the various ports Ileading into the valve chamber from the passages, 13, 14, 15, 16 and 17. The exact manner in which the valve functions can be most easilyexplained' by following through the operation' of the device.

In the position shown in Figure 19, the valve 18 is in its lowermost position and the pocket 24 in the valve 18 connects the passage 1 7 carrying operating fluid under pressure to passage 14 and leading to the top of the motor cylinder 2. At theA same time pocket 25 connects the passage 13 leading from the bottom of the motor cylinder to the passage 15, leading into the exhaust passage 10. High pressure fluid from tube 11 is thereafter applied to the upper side of the motor piston 4 and the latter is maintained in its lowermost position. With the valve 18 in its lowermost position, as shown, the pocket 24 also registers with a port connected with a passage 26 in the piston rod which communicates through asecond port with the extreme lower end of the valve chamber 6 below the valve 18. High pressure fluid istherefore applied against the lower end of the valve 18 and Amoves'the latter upwardly. At the same time the fluid in the upper endof the, valve chamber 6 above the valve 18 is exhausted through a passage 27 in the piston rod and .through pocket 25 of valve 18 an'd exhaust port 15 into the exhaust passage 10.v 'Ihe pressure oi' the operating fluid being substantially greater than that of the exhaust fluid. the valve 18 moves upwardly.

Upward movement of the valve first carries the shoulder 20 past the port connected with the passage 14, thus cutting off the supply of operating fluid to the' upper end of the motor cylinder 2 and then connects the port at the upper end of passage 14 through pocket 23 with the exhaust passage 16, as shown in Figure 20. At the same time, the

lupward movement of valve 18 brings the center -limit of its stroke since the ports leading into the valve chamber 6 have appreciable longitudinal dimensions. As a result, for a short interval bcvfore-the valve 18 reaches the upper limit of its stroke operating fluid is applied simultaneously both to the underside of the motor piston l and the valve 18. v

If the design of the pump were not such as to prevent it, the piston assembly might begin to move upward before the valve completed its upward movement. timohpremature movement of the piston cannot take place, however, for the reason'that a greater differential between the pressure of the operating fluid and emaust fluid is required to move the piston assembly than is required to Smove the valve; furthermore, this pressure differential cannot increase materially above that necessary to move the valve as long as the latter is free to move.

The differential pressure between the operating and exhaust fluids required to move the valve is less than that required to move the piston assembly for the reason that the ratio of the areasof the opposite valve faces exposed to operating fluid and exhaust'uid, respectively. is greater vthan the ratio of opposed areas of the piston "ofV pump piston 3 are exposed to the pressure of the exhaust fluid in exhaust passage 10. The lower face of the pump piston and the upper end of the piston rod 5 are exposed only to the pressure of the fluid in the well which is relatively l small and`may be disregarded.

As va result of the lesser pressure required to move the valve 18 than the piston assembly, the valve continues its upward movement substantially to the upper end of the valve chamber 6. When the valve can move upward no further, however. there is then no outlet for the operating fluid which is being constantly pumped down through tube' 11 and passage 17 except through passage 13 to the lower face of the motor piston 4. The pressure of the operating fluid therefore immediately rises to a value sumcient to move the-piston assembly and it thereafter moves the piston assembly into its uppermost position as shown in Figure 20. During this upward movement, the exhaust fluid in the motor cylinder 2 above the motor piston 4 is exhausted through passage 14 and past pocket 23 on the valve out through port 16 into the exhaust passage 10.

vTo prevent the valve 18 from impacting directly against the metal end wallof the valve chamber 6 on its upward movement the passage 27 in the piston rod 5 ls so dimensioned that when the piston rod is in its lowermost position, as shown in Fig. 19, the upper end of the passage 27 is slightly below the upper end of the valve chamber 6. Therefore when the valve 18 moves upwardly it seals the passage .27 slightly before the valve reaches the vend of the valve chamber. This traps a small amount of exhaust fluid between the upper end of the valve and the upper end of the valve chamber which serves as a cushion to halt the valve before the latter impacts with the end of the valve chamber. However, as soon as the piston assembly begins its subsequent upward movement the passage 27 again registers with the space above the valve 18 to permit the exhaust of the fluid formerly trapped 'above the valve, thereby permitting the valve to move positively but slowly into its extreme uppermost position. With both the valve and piston assemblies in their extreme uppermost positions, as shown in Fig. 20, operating fluid is supplied through passage 17, the valve pocket 24, and the passage 26 of the piston rod to the upper end of the valve chamber. At the same time the lower end of the valve chamber is connected through exhaust passage 28 in the piston rod and the lower valve pocket 2'3 with the exhaust port 16. The valve therefore moves downward in response to the differential pressure applied to the opposite ends thereof precisely as it moved upward on the previous stroke. When the valve reaches the lower end cf its stroke it again applies fluid from passage 17 through pocket 24 and passage 14 to the upper end of the motor piston 4 and simultaneously connects lthe passage 13 leading froml the lower end of motor cylinder 2 through valve pccket 25 and exhaust port 15 to the exhaust passage 10.

The piston assemblytherei'ore moves downward and exhaust fluid are applied to the substantially equally opposed end faces on the valve l8r. whereas the operating iluid is applied only to the upper face of the motor piston 4 and both the lower face of piston 4 and the lower face of the pump piston 3 are exposed to the pressure of exhaust fluid. Of course during the downward movement of the pump piston 3 the upper face of the pump p'son is exposed to the pressure of exhaust fluid as well as the lower face, but, as has been previously pointed out, the area of the piston rod 5 is made substantially equal to half the area of the lower facel of the pump piston 3. il'herefore the exhaust fluid` is applied to twice the area of 'the lower face of pump piston 3 as on the upper face. The overall result is that on the downward stroke of the pston assembly the downward force developcd by pressure of operating fluid on the upper face of the .motor piston 4 is opposed by a force resulting from the application of exhaust fluid to substantially twice the area of under surface ofthe piston assembly (the lower face of the motor piston 4 plus half the area of the face of equal volumesof exhaust fluid from the motor cylinder 2 on both strokes, since the areas of the upper and lower faces of the motorpiston 4 are equal.. Likewise the pump discharges equal volumes of pumped iluid on both strokes because 'the area of the piston rod 5 is half the area of the lower face of the pump piston 3. Since the valve 18 isl symmetrical in structure, the exhaust fluid discharged from the opposite ends thereof on different strckes is equal in volume.

Pumps of the general type to which this invention relates, must be suillciently small in overl all diameter to be lowered through va vwell casing which in many instances is only 4 or 5 inches in diameter or even smaller. The problem of design of a pump functioning as described in connection with the schematic view shown in Figures 19 and 20 is, therefore, not a simple one. It will be observed irom Figures 19 and 20 that the passages 13 and 10 must extend down past the motor cylinder 2 and that the passages 17, 13, 14 and 10 all extend down past the valve chamber 6.

Construction of a practical pump I have found it most satisfactory to form the body of the pump, which defines thepump and motor cylinders, the valve chamber and the piston rod guides in between the cylnders and the valve chamber, from short liners machined from castloo ings and having the passages 13, 14 and 10 formed in the walls of the liners.

Thus referring to Figures 3 to 8, inclusive, I have shown a plurality of separate liners 29, 30, 31, 32, 33, 34, 35. 36, 37, 38, 39, 40, 41, 42, 43, and 44 all compressed end to`end and maintained in alignment within an outer casing designated generally at 45. The outer casing 45 may itself comprise a plurality of relatively short sections screwed together. Thus, in Figures 3 to 8 the outer casing 45 has been shown as comprising an upper section 46, intermediate sections 47, 4 8 and 49, respectively. anda lower section 50.

Referring to Figure 3, the outer casing section 47 is provided with an inwardly projecting shoulder 52 bearing against the shoulder 51 on the upper liner 29 which transmits the compression exerted downwardly on the end of the series of liners to the outer casing 45. Likewise, the lowe'rmost liner 44 (Fig. l7) is provided with outwardly projecting shoulder 53 which bears against an inwardly projecting shoulder 54 in a coupling member 55 positioned between and joining sections 49 and 50 of the outer casing 45;

The upper and lower faces of the l'ners 29 to y lgrooves provided therefor at the junction of'each pair of liners. seal around the l'ne of contact of each adjacent pair of liners to prevent leakage to the space within the outer casing 45.

To connect the outer casing 45 to the tubing 12 for supporting the latter and for exhausting fluid to the surface, the upper section 46 (Fig. 3) .of the casing is threaded onto the lower end of a nipple 58, the upper end of which (Fig. 2) is joined by a threaded coupling 59 directly to the lower ond of the tubing 12.

To form vthe necessary high-pressure fluid connection between the pressure fluid tubing 11 extending down (Fig. 2) from the surface of the earth within the exhaust fluid tube 12, the lower These aligning rings 57 form a end ci tubing ll is joined by a threaded coupling 60 to the upper end of a sleeve 6i. which extends within and in telescopic engagement with a sleeve 62 which in turn is threaded at its lower end onto a nipple 63 which in turn is joined to the 'upper section i6 oi the pump casing e5 by screwthreads 6ft. 'lllie'lower lface of sleeve 6l is tapered and ground to form a fiuid-tight connesn tion with a` correspondingly tapered upper end of the nipple 63. Under normal operating cannl ditions the weight of the pressure fluid tubing l1 maintains the lowerend ci sleeve 6l in fluidn tight engagement with the nipple t3.

The path ci operating fluid transmitted down through the tubing l1 may be traced from. tub ing 1l down 'through the sleeve 6l, through the' nipple 63 andinto the upper end of the top liner 29 from which it enters a port 65 leading through passages in the liners to the valve chamber. The passages from the port 65 to the valve chamber will be described at a later point.

.as shown in liiig. 3, the central cavity in the upper liner 29 extends completely therethrough but is normally sealed at a point below the port 65 by a plug 86. The lmction of this plug will described later.

lt will be observed from an inspection of Figs. 8, e and that the liner 3l is drilled to pro vide the guide 7 for the upper end ci the piston rod designated generally at 5, that the lower tace ci the liner 32, which is likewise drilled to receive the piston rod 5 iorms the upper end ci' the valve chamber 6, that liners 33, 34, 35 and 86 are drilled to provide a larger central cylindrical passage constituting the walls oi the valve chamber 6, and that the upper face of the liner 87 constitutes the lower end wall oi valve chamber 6.

Liners 37 and 38, like the liners 31 and 32, are drilled to snugly receive the piston rod 5 passing therethrough and the lower end of liner 88 constitutes the upper end of the motor cylinder 2. The walls of motor cylinder 2 are formed by central apertures oi suitable size in the liners 39, d0, 4l and d2. The upper end of liner 43 constitutes the lower end wall ci the motor cylin= der 2, and the central aperture in liners 43 and la is dimensioned to snugly nt the piston rod 5, these liners constituting the piston rod guides between the lower end of the motor cylinder 2 and the upper end of the pump cylinder l.

The wall of the pump cylinder or barrel itlf is constituted by a sleeve 87 which is compressed between the-lower end oi liner ed and a plug 68. The plug 68 is in turn maintained in compression against the lower end of sleeve 67 by a bushing 74 screwed into the lower end oi the bottom casing section 50.

The upper end of the sleeve 67, constituting the wall of the pump cylinder, is flared outwardly at its upper end, as shown in Fig. 7, to provide a iree passageway ior exhaust fluid and is enlarged at the lower end, as shown in lig. 8, to provide room i'or a conventional inlet valve 69 comprising a ball 7o, a seat 7i' therefor, and a cage 72. The seat 71vis retained in position against the top ofthe plug 68, constituting the.

lower end wall of the pump cylinder, by the cage 72 which is screwed onto an upwardly projecting flange 73 in the plug 68. The inlet passage for huid to be pumped is formed by a central aperture 75Jin plug 68 extending down below Ythe valve seat 7l and communicating with lthe exterior of the casing 45. My device. is designed particularly for use in oil wells and it is de- Lerma? 'sirable that provision be made for the separation oi gas from the oil to as large an extent'as possible beforel the oil enters the pump cylinder. For this reason l prefer te attach a conventional gas anchor to the lower end oi the pump. In Figure 8 I have shown this gas anchor as coni= prising a perforated tube 76, the upper end oi which is threaded into bushing 7a.

lihe tubing 76 extends some distance below the bushing 7a and is attached at its lower end to a cap member 77 which is of slightly larger interior diameter than the external diameter of tubing 76 and extends upwardly about tubing 76. l piece of tubing 78 is threaded int-o the lower end of the plug 68 and extends downward some distance into the tubing 76. Anchors of the type described are old and well-known in the art and their operation is well understood by those skilled` in the art.

y The piston assembly The piston rod which has heretofore been reierred to generally by the reference numeral 5, is preferably tubular in construction and as shown in the drawings comprises a tube 79 closed at its upper end by a plug 80 threaded therein and closed by and attached to a plug 8l at its .lower end which likewise is threaded into the tube 79. The lower plug 91 also constitutes a means of attaching the tube 79 to the upper end ci the motor piston 82. -Thus the lower end or" plug 81 is enlarged to form a-ange A83 iitting into the hollow upper end of piston 82. A bushing 84 is screwed into the upper end of the piston 82 about the plug 8l and bears against the upper face of ange 83.

The motor piston, comprising the member 82, is symmetrical in construction and it is joined at its lower end to a tube 85 in exactly the same manner as it is joined to tube 79.. Tube 85 constitutes the portion. of the piston rod extending between the motor piston, designated generally at 4, and the pump piston designated generally at 3. Pump piston 3 comprises a sleeve 86 (Figs.

7 and 8) which is joined by screw threads at its upper end to a valve cage 87. Valve cage 87 is provided with a shoulder 88 which engages with and holds in position a valve seat 89 which cooperates' with a valve ball 99 positioned within the valve cage 87. 'The valve cage 87 is provided at its upper end with an inwardly projecting flange 911 which is clamped between the lower end of tube 85 and a shoulder 92 on the lower end of a plug 93 screwed into the lower end oi tube 85.

The valve cage 87 is of open construction to provide passages, one of which is shown at 94, for the passage of fluid from the hollow piston to the space in the cylinder thereabove surrounding the tube 85.

I have shown the pump piston 3 provided with a second valve positioned at its lower end, this valve comprising a seat 95, a ball 96 and a cage 97. The cage 97 is-provided with an outwardly extending flange 98 on its lower end which rests against a shoulder formed by enlarging the lower end oi the sleeve 86 constituting the main body of the piston 8, and both the valve seat and cage -97 are held in position by a bushing 99 screwed into the lower end .of the piston sleeve 85.

Referring to Figs. 4 and 5, the exhaust pasi sages for exhausting fluid from the respective upper and lower ends of the valve chamber 6 are constituted by grooves 27 and 28 in the outer surface of the tube 79 constituting the portion of the piston rod adjacent the valve. The pamagc 26 (Fig. 19) within thepiston rod for supplying l high-pressure fluid to operate the valve, comprises the central passage within the tube 79, ports 100 (Fig. 4) and 101 (Fig. 5) being provided at the proper longitudinal points to register with the 'upper end of the valve chamber 6 and the pocket 24 of the valve, respectively; when the pis-.

s1, respectively (Figs. 4 and s), the ports 10o and 101 constitute the only openings leading to and from the passage 26. f

The valve structure ber. The sleeve'is .provided with shoulders 22,A

21, 20 and 19, respectively, which define the three J pockets 25, 24 and 23, previously referred to in connection with Figs. 19 and 20. Cylindrical webs 102, 103 and 104 join the respective shoulder portions 22, 21, 20 a d 19 of the valve. Web portions 102 and 104 ave their inner walls continnous with the inner walls of the shoulder por- -s-tionlreh they connect so that they seal with the surface of the piston rod, but they center web .103 is cutaway on the inside and provided with numerous perfor-ations to permit thev free passage 9 of fluid from the valve pocket 24 into the ports 100--101 in the piston rod tubing 79. The upper vweb 102 is also provided with ports 1 05 to permit the free passage of fluid from the grooves 27 to the pocket 25 and the lower web 104 is provided' ,1L- with ports 106 adjacent its lower end to permit the free passage of fluid from grooves 28 to pocket Duringl operation of the pump, the movement of the valve is positively controlled by the 5; fluid pressure applied to one or the other end thereof. However, it is desirable that whenthe pump is not in use, as during transportation or following its construction but preliminary to its use in a well, the valve 18 should be maintained g in one end position. Otherwise, the valve might b jolted into such a position that the pump would not automatically start operating. To normally" retain the valve in one end position, the liner 33 (Fig. 4) is provided withfour ball @y detenta (Fig. 13) which are mounted in radial apertures extending outwardly in the liner 33 from the central passage therein defining the wall of thel valve chamber and are normally urged inwardly against the valve by springs.

Eg- Thus, referring to Fig. 13, each ball 107 ispositioned in a horizontal passage 108 and has mounted back of it a small spiral spring 109 whichconstantly urges the ball inward into engagement with the valve. Each spring 109 is retained in position by a screw plug 110 whichl closes the outer end ci the passage 108. The upper web 102joining the shoulders 22 and 21 of the valve 18 (Fig. 4) is provided with surface depressions 112 and111, respectively, the depression 111 lying 2J opposite the ball detents 107 when the valve is Lavigvav 4has been fully explained withreterence to the (referring to Fig.

in lowermost position, as 'shown in Fig. 4, and the depression 1'12 being"juxtaposed-toiiliegbilv^` detent 107 vwhen -the valve is in uppermost positin.

'I'hese detents and the cooperating depressions. 30 111 tend to retain thev valve in its end positions but they do not offer sufllcient restraining force to prevent the free `movement oi' the valve in response. to the dinerential fluid pressures normallyacting upon the valve to move it in the desired manner.

Operation.' of the practicalpump Since the theoretical operation ofthe pump schematic diagram of Figs. 19 and 20, and the structure of a practical embodiment of the' pump has been fully described, and the essential elements of the practical embodiment corresponding to the elements of the schematic diagrams have been pointed out, the operation of the practical embodiment of the pump will be fully apparent when the courses of the duid passages have been traced.

Thus, referring to Fig. 19, passage 17 conveys high-pressure uid from the pressure tubing 11 to they center pocket 24 of the valve 18. In the practical pump disclosed, the high-pressure fluid from tubing 11 flows down through the sleeve' 61 through the nipple 63 into the upper end of liner 29 and thence, through horizontal passage 65 (referring to Fig. 12) into vertical passages`113 formed within the wall of liner 29.

Referring now to Fig. 9, the passages 113 extend down through liners 29, 30, 31, 32, 33 and 34, 1&0 These passages terminate at the lower end oi.' liner 34 (since the corresponding passages are not provided in the next lower liner 35) and, 1,5), 'are connected at this point by ports 114 to the valve chamber 6. Thus the passages 113, constitute the equivalent of passage 17 in Fig. 19.

Now tracing the course of the passage identified by the reference numeral 13 in Figs. 19 and 20, we have (Fig. 14) a pair of ports 115 extending outwardly from the central aperture through liner 34 forming a portion of the cylindrical wall of the valve chamber 18. The outer ends of ports 115 communicate with a pair of vertical passages 116 (Fig. 10) which extend down through liners 34, 35, 36, 37, 3 8, 39, 40, 41 and 42 to the lower end .of the motor vcylinder 2 at which point passages 116 terminate and communicate with ports 117 which extend into the lower end of the motor cylinder. The passages 116 in Fig. 10 therefore correspond to the .passage 13 in Figs. 19 and 20. The passage in the practical pump corresponding to passage 14 (Figs. 19 and 20) extending from the valve chamber to the upper end of the motor cylinder, is constituted by passages 118 (Fig. 135 9) which are formed in the walls of liners 35, 36,

. 37 and 38 and communicate at their upper ends with the valve chamber-6 through ports 119 and with, the upper end of the motor cylinder through ports 120 at vtheir lower ends. 'I'he relative positioning of the passages 118 and the ports 119 and 120 is shown in the cross sectional views of Figs. 16 and 17. It will be observed from these figures, and from Fig; 9, that the passages 1-13 and 118 are inthe same vertical plane.

The passage corresponding to exhaust passage 10 in Figs. 19 and 20, is designated in Figs. 3 to 7A and Figs 12 to 18 by the reference numeral 121.

It comprises two vertical passages extending normar and rod ,141 to be carried up out of the wellwith the inner tubing 11.

'I'he removal of plug 66 leaves an open passageway between the outer tubing 12 and the pasing 11 and the outer tubing l2 andthe pump.y

I claim:`

1. In a fluid operated pump. an exhaust conduit for discharging exhaust fluid under pressure, a source of constant flow of operating fluid, a

pump cylinder and av motor cylinder, pump andmotor pistons in said respective cylinders, conduits connecting said motor cylinder to said source of operating fluid and said exhaust conduit and connecting said pump cylinderf to said exhaust conduit, a common piston rod to which said pistons are connected, a piston valve for controlling flow of fluid between said motor cylinder and said source and'between said motor cylinder and said exhaust conduit, said valve being operable through a stroke` between two end positions to admit fluid from said source to opposite ends of said motor cylinder during substantial` portions of successive strokes of said valve, auxiliary valve means to alternately admit fluid from said source to opposite ends of said piston valve whereby operating fluid is supplied simultaneously to the piston of said 'motor and to said piston valve during at least a. portion of the stroke of the latter, said valves also operating to expose the opposite surfaces of said valve and motor piston, respectively, to the pressure of said exhaust fluid, the ratio of the surfaces of said piston valve exposed to operating fluid and exhaust fluid, respectively, being substantially the same as the ratio of the surfaces of said motor piston exposed to operating fluid and exhaust fluid, respectively, and said pump being operative to deliver substantial quantities of' pumped fluid into said exhaust conduit against the pressure of said exhaust fluid, on both strokes, whereby the differential pressure between said operating uid and exhaust fluid necessary to move said pistons through a stroke is always greater than the differential pressure necessary to move said piston valve through a stroke.

2. In a fluid operated pump, an exhaust conduit for discharging exhaust fluid under pressure,

a source of constant flow of operating fluid, a pump cylinder and a motor cylinder, pump and motor pistons in said respective cylinders, conduits. connecting said motor cylinder to said source of operating fluid and said exhaust conduit and connecting said pump cylinder to said exhaust conduit, a common piston rod to which said, pistons are connected, a piston valve for controlling flow of fluid between said motor cylinder and said source and between said motor cylinder and said exhaust conduit, 4said valve being operable through a stroke between two end positions to admit fluid from said source to op- -posite ends` of said motor cylinder during substantial portions of successive strokes of said valve, auxiliary valve means to alternately admit fluid from said source to opposite ends of said piston valve whereby operating fluid is supplied simultaneously to the piston of said motor and to said piston -valve during at least a portion of the stroke of the latter, said valves also operating to expose the opposite surfaces of' said valve and' motor piston, respectively, to the pressure of said exhaust fluid, the --ratio oi' the surfaces of said piston valve exposed to operating fluid and ex.

haust fluid, respectively, being substantially the saluel as'the ratio of the surfaces of said motor piston exposed tooperating fluid and exhaust fluid, respectively, said pump cylinder having an inlet valve in one end communicating with fluid to be pumped, an exhaust port in the other end,

said pump piston having a vaived opening to said pump delivers substantially equal volumes of fluid on both strokes. Y

- 3. In a fluid operated pump, an exhaust conduit for discharging exhaust fluid under pressure, a source of constant now of operating fluid,l a pump cylinder and a motor cylinder, pump and motor pistons in said respective cylinders, conduits connecting said motor cylinder to said source of operating duid and said exhaust vconduit and connecting said pump cylinder to said exhaust conduit, a common piston rod to which said pistons are connected, a piston valve for controlling flow of fluid between said motor cylinder and' said source and between said motor cylinder and said exhaust conduit, said valve being `operable through a stroke between two end positions to admit fluid from said source to opposite ends of said motor cylinder during substantial portions of successive strokes of said valve, auxiliary valve means to alternately admit fluid from said source to opposite ends of said piston valve whereby operating fluid is supplied simultaneously to the plston of said motor and to said piston valve'during at least a portion of the stroke of the latter, said valves also operating to expose the opposite .surfaces of' said valve and motor piston, respectively, to the pressure of said exhaust fluid, the ratio of the surfaces of said piston valve exposed to operating fluid and exhaust fluid, respectively, being substantially the same as the ratio of the surfaces of said motor piston exposed to operating fluid and exhaust fluid, respectively, said pump cylinder having an inlet valve in one end communicating with fluid to be pumped, an exhaust port in the other end, said pump pstonhaving a valved opening to admit fluid from the valve end of the cylinder to the ported end, and said pumppiston having a piston rod of substantially half the cross sectional area of the piston face, said piston rod extending through the ported end of said cylinder, wherebysaid pump delivers substantially equal volumes of fluid on both strokes, the outer o1' substantial cross sectional area relative to` the area of said piston extending upwardly from said piston through the end of and above 'said pump cylinder, a motor cylinder positioned above said pump cylinder and in alignment therewith,

a m'otor piston in said motor cylinder and attached to said'piston rod, said piston rod extending through the end walls of said motor cylinder both above and below, a valve chamber above said motor cylinder, and a piston valve concentrically positioned about the upper end of said piston rod within said valve chamber, auxiliary valve means including as an element thereof the upwardly ex- I tended portion or the piston rod within the valve chamber for selectively supplying operating duid bil under pressure to opposite ends 'of said piston valve, and means including said piston valve for successively connecting opposite ends of said mo tor cylinder to a source oi operating fluid under pressure and to said exhaust passage respectively.

5. In a duid operated' pump of the type described, adapted to be submerged in fluid to be pumped, a tubular shell having a pump cylinder therewithin at the bottom, a valved 'piston in the cylinder, an inlet valve in the bottom of the cylinder, a discharge port in the upper end oi? the cylinder, a piston rod extending upwardly from the piston through the upper end wall of the cyl= inder and terminating within said tubular shell, said piston rod having substantially hall the cross sectional area of said piston whereby the pump delivers substantially equal volumes of uid in to said exhaust port on both strokes, means conr-` prising a motor and a valve therefor positioned above said pump cylinder for reciprocating said piston rod, said rod extending completely through the motor and valve and having its upper end exposed to the pressure or the fluid in which the pump is submerged.

6. In a duid operated pump of the type described, adapted to be submerged in duid to be pumped, a tubular shell having a pump cylinder therewithin at the bottom, a valved piston in the cylinder, an inlet valve in the bottom of the cylinder, a discharge port in the upper end of the cylinder, a piston rod extending upwardly from the piston through the upper end wall of the cyl inder and terminating within said tubular shell, said piston rod having substantially half the cross sectional area of said piston whereby the pump delivers substantially equal volumes of duid into saidexhaust port on both strokes, means com prising a motor and a valve therefor positioned above said pump cylinder for reciprocating said piston rod, said rod extending completely through and beyond the motor and valve, a piston rod guide above said motor and valve and sealing with the portion of said piston rod extending therethrough, an inner wall within said shell defining an enlarged central chamber above said guide and communicating therewith, said wall also deiining, together with the tubular shell of the pump, an annular chamber surrounding said central chamber, and said inner wall and shell having holes extending therethrough lor permitting fluid flow from the exterior of the pump to and froml said central chamber through said annular chamber as the piston rod reciprocates, thereby exposing the-upper end of said rod to the pressure of fluid in which the pump is submerged, said annular chamber serving as a trap for solid matter in said iiuid.

'7. In a high pressure pump comprising v an elongated'member having therein elongated passages for containing uid `at high pressures, the structure comprising an outer tubular shell, a

'l plurality of liners of smaller external diameter than the internal diameter of said shell compressed end to end within said shell, said liners having longitudinal interconnecting passages therethrough defining the high pressure fluid passages of said pump and having their juxtaposed surfaces ground to seal with each other about sa'd passages, and a tightly ntting ring surrounding the ends of adjoining'liners to provide an auxiliary -sealbetween said liners, and to align said liners,

normar Vouter tubing, a coupling in said outer tubing pos= tioned above said shell and defining a chamber between the juxtaposed ends oi the outer tubing which it connects oi larger diameter than the inner dieter of said outer tubing, a female sleeve rigidly attached to and extending upwardly from said shell within said outer tubing, having a smooth cylindrical inner surface constituting a portion of a high pressure passage for delivering operating duid to the mechanism within said shell, the upper end of said female sleeve being tiered outwardly and terminating within said chamber, and a male sleeve adapted to be rigidly attached to the lower end of said centrali tubing and having a smooth exterior cylindrical surface lor telescoping within and sealing with said female sleeve, whereby the riuid connection between said central tubing and the high pressure passage of said pump may be made or broken by merely lowering said central tubing frornthe surface, the

outside diameter of the dared end of said female sleeve being greater than the inside diameter of said outer tubing but less than the diameter ci said chamber defined by said coupling.

e. In a fluid operated pump of the type described, comprising a tubular shell containing a pumping mechanism supplied with high pressure operating iiuid through small central tubing ex tending to the surface and delivering exhaust fluid and pumped iiuid to the surface through larger outer tubing surrounding said central tubing, means for rigidly attaching said shell to said outer tubing, a female sleeve rigidly attanhed to and extending upwardly from said shell within said outer tubing and having a smooth cylindrical inner surface constituting a portion of a high pressure passage for delivering operating uid to the mechanism within said shell, and a male sleeve adapted to be rigidly attached to the lower end oi said central tubing and having a smooth exterior cylindrical surface for telescoping within and sealing with said female sleeve, whereby the fluid connection between said central tubing and the high pressure passage of said pump may be made or broken bymerely lowering or raising said centrai tubing from the surface, said female sleeve being perforated at a level intermediate its upper and lower ends whereby communication may be established through said perforation between said 'central tubing and the outer tubing by raising said sleeve to uncover said perforation without completely withdrawing the male sleeve from the female sleeve.

lo. in a fluid operated pump or the type de scribed, comprising a tubular shell containing a pumping mechanism supplied with high pressure operating iluid through small central tubing extending to the surface and delivering exhaust fluid and pumped fluid to the surface through larger outer tubing surrounding said central tubing, means for rigidly attaching said shell to said outer tubing, a-female sleeve rigidly attached to and extending upwardly from said shell within said outer tubing and having a smooth cylindrical er surface constituting a portion oi a high vloo pressure'passage for delivering operating fluid to the mechanism within. said shell, and a male sleeve adapted to be rigidly attached to the lower end of said central tubing'and having a smooth exterior cylindrical surface for telescoping within and sealing with said female sleeve, whereby the fluid'connectiorr between said central tubing and the high 4pressure passage of said pump may be made or broken by merely lowering or raising said central tubing from the surface,'said female sleeve being perforated at a level intermediate its upper and lower ends, means for resisting upward movement of the lower end of said male sleeve beyond a level between said perforation and the upper end of said female sleeve, comprising an inwardly projecting shoulder on the lower end of said male sleeve, and a rod positioned-within said male sleeve and having outwardly projecting shoulders on its upper end'for engaging with said inwardly projecting shoulders on the lower end of said male sleeve upon predetermined upward movement of the latter, and means for releasably anchoring the lower end of said rod to the body of the pump.

11. In a fluid operated pump ofthe type described, comprising a tubular shell containing a pumping mechanism supplied with high pressure operating iiuid through small central tubing extending to the surface and delivering exhaust fluid and pumped fluid to the surface through larger outer tubing surrounding said central tubing, .means for rigidly attaching said shell to said v outer tubing, a female sleeve rigidly attached to and extending upwardly from said shell within said outer tubing and having a smooth cylindrical said central tubing from the surface, said female l sleeve being perforated at a level intermediate its upper and lower ends, means for resisting upward movement of the lower end of said male sleeve beyond a level between said perforation and the upper end of said female sleeve, comprising an inwardly projecting shoulder on the lower end of said male sleeve, and a rod positioned within said male sleeve and having outwardly projecting shoulders on said upper end for engaging with said inwardly projecting shoulders on the lower end of said malesleeve upon predetermined upward movementof the latter, means defining a low pressure passage in said pump body below said high pressure passage and communicating with the exterior of said pump shell, means dening a central, vertical, restricted passage connecting said low and high pressure passages and having a tapered seat at its upper end, a tapered plugl on the lower end of said rod for sealing said restricted opening when said rod isin lowermost position, and stop means on said rod engaging with said male sleeve when the latter is in lowermost position for maintaining the rod in lowermost position.

12. In a fluid operated pump of the type described, comprising a tubular shell containing a pumping mechanism supplied with high pressure operating uid through small central tubing extending to the surface and delivering exhaust fluid and pumped fluid to the surface through larger outer tubing surrounding said central tubing, means for rigidly attaching said shell t'o said outer tubing, a female sleeve rigidly attached to and extending upwardly from said shell within said outertubing and'having a smooth cylindrical inner surface constituting a portion of a high pressure passage for delivering operating iiuid to the mechanism within said shell, and a male sleeve adapted to be rigidly attached to the lower lend of said central tubing and having a smooth exterior cylindrical surface for telescoping within and sealing with said female sleeve, whereby the fluid connectionl between said central tubing and the high pressure passage of said pump may be made or broken by merely lowering or raising '90 said central tubing from the surface, said female sleeve being perforated at a level intermediate its upper and lower ends, and means for resisting upward movement of the lower end of said male sleeve beyond a level between said perfora-V tion and the upper end of said female sleeve, comprising an inwardly projecting shoulder onV the lower end of said male sleeve, and a rod positioned within said male sleeve and having outwardly projecting shoulders on its upper end `for 1'0 engaging with said inwardly projecting shoulders on the lower end of said male sleeve upon predetermined upward movement of the latter, means defining a low pressure passage in said pump body below said high pressure passage and com'- 105 municating with the exterior of said pump shell,I means defining a central, vertical, restricted passage connecting said low and high pressure passages and having a tapered lseat at its upper end,

a tapered plug on the lower end of said rod for 1'10 sealing said restricted openlngwhen said rod is in lowermost position, the lower end of said plug comprising means extensible through said restricted v passage Aand resiliently engaging the lower end of said restricted passage to resist upward movement of said plug and rod but'releasableupon application of a predetermined lifting force to said rod through said central tubing.

13. In a fluid operated pump `oi' the type described, comprising a tubular shell containing 1'20 a pumping mechanism supplied with high pressure operating fluid through small central tubing extending to the surface and delivering exhaust iiuid and pumped fluid to the surfacey through larger` outer tubing' surrounding said 125 central tubing, means for rigidly attaching saidl shell to said outer tubing, a female sleeve rigidly attached to and extending upwardly from said shell within said outer tubing and having a smooth cylindrical inner surface constituting a 13g portion of a high pressure passage for delivering operating. fluid to the mechanism within said shell, and a male sleeve adapted to be rigidly attached to the lower end of lsaid central tubing and having a smooth exterior cylindrical surface for telescoping within and sealing with said female sleeve, whereby the fluid connection between said central tubing and the high pressure passage of said pump may be made or broken by merely lowering or raising said central tubing 14@ from the surface, said female sleeve being per- Afor-ated at a level intermediate its upper and lower ends, and means for resisting upward movement of the lower end of saidmale sleeve beyond a level between said perforation and the upper end of said female sleeve, comprising an inwardly projecting shoulder on the lower end of said male sleeve, and a rod positioned within said male sleeve and having outwardly projecting shoulders on its upper end for engaging with plus on the 4lower -.end o: said rqdfor Sealing said restricted passage when :saidrodis'in lower-j'v mostl position`-and stop meanson said rod erf-f gagng' with said m'alefsleeve whenj'the llatter is in 'lowerniost position for "maintaining the rod4 in lowermo'st position, said stop means v comprising' a plurality4 of radiating arms foiicent'erinjg isc 

